1. Technical Field
The present invention relates to a terminal for being installed in an isolating housing to form an assembled electrical socket connector and, more particularly, to a female terminal that is made of metal and set to permit a slender pin to plug in and contact conductively.
2. Description of Related Art
Electrical socket connector is known as an indispensable part for connecting multi-core cables of 3C products and household appliances for signal communication. Conventional electrical socket connectors can be principally classified into either male connectors or socket connectors. A male connector typically comprises a plurality of pins and a socket connector typically comprises a plurality of terminals corresponding to said plural of pins so as to permit the pins of the male connector to plug in and contact conductively.
Compared with a male connector, a socket connector requires a more complex manufacturing technique. The critical component of such socket connector is the terminals therein, which preferably have small-volume; provide guide function to the pin that are to be plugged in; and provide appropriate clamp force to ensure the connection and conduction between the terminals and the pins plugged therein. Thus, a terminal made of a metal sheet in one-piece construction has become the main stream of the development of the art.
In prior arts, U.S. Pat. No. 5,720,634 discloses a female terminal formed in one-piece construction. In such prior-art female terminal, an inner tube and an outer barrel are provided at the portion in contact with a pin, wherein the outer barrel is connected to a neck of the female terminal, while the inner tube is formed by folding a metal sheet inwardly within the outer barrel. The inner tube is substantially composed of a plurality of spring elements bent with a mold in order to clamp a pin. Since the spring elements are formed as cantilevers, the inner tube is with only one end folded as a round gateway while the opposite end is opened as a free end, and thus full control of configuration of such prior-art female terminal is difficult to achieve.
In prior arts, U.S. Pat. No. 6,152,787 also provides a female terminal formed in one-piece construction. In such prior-art female terminal, an inner tube and an outer barrel are provided at the portion in contact with a pin, wherein the inner tube is connected to a neck of the female terminal, while the outer barrel is formed by folding a metal sheet to enclose the inner tube. The inner tube is substantially composed of a plurality of spring elements bent with a mold in order to clamp a pin. Since the spring elements are formed as cantilevers, the inner tube is with only one end folded as a round gateway while the opposite end is opened as a free end, and thus full control of configuration of such prior-art female terminal is difficult to achieve. Actually, the configurations of U.S. Pat. No. 6,152,787 and U.S. Pat. No. 5,720,634 are very similar. The only difference therebetween is that U.S. Pat. No. 5,720,634 has the outer barrel connected to the neck of the female terminal and the inner tube is formed by folding a metal sheet inwardly within the outer barrel, while U.S. Pat. No. 6,152,787 has the inner tube connected to the neck of the female terminal, while the outer barrel is formed by folding a metal sheet to enclose the inner tube.
Further, in prior arts, U.S. Pat. No. 6,358,104 discloses another female terminal formed in one-piece construction. In such prior-art female terminal, an inner tube and an outer barrel are provided at the portion in connection with a pin wherein the inner tube is connected to a neck of the female terminal, while the outer barrel is formed by folding a metal sheet to enclose the inner tube. A plurality of spring elements are deposited in the inner tube and each of the spring elements has a wavy profile in the middle portion thereof. Thereby, when the inner tube is later bent into a shape of a round gateway by a mold, the wavy portion of each said spring element leans toward the inner tube axis automatically under the bending force so as to provide a clamp force to a plugged pin. Meantime, as the U.S. Pat. No. 6,358,104 has both ends of the inner tube formed as round gateways by bending a metal sheet, both ends are not shaped as cantilevers. Thus, compared with U.S. Pat. No. 6,152,787 and U.S. Pat. No. 5,720,634, it achieves superior structure strength.